You can join a Google Meet meeting without a Google account if the meeting creator enables the “Anyone with the link can join” setting, or if they accept you when you click the link.
It's been over 6 months since I've looked into this, so it's possible my info is out of date - but the “Anyone with the link can join” setting is only available to people with a paid Google business account. Nobody in my department had anything like that
https://support.google.com/meet/answer/9303069?hl=en&co=GENI...